pratt



a. R. PRATT.

FIRE POT.

APPLICATION FILED SEPT.26| I918.

Patented Apr. 11, 1922.

GEQRGEQROBE PRATT, or winnirseg iiraivrronmcaiirana.

T aZZIw homit may comm Be it known that I, GEoiieE Ronnar Pm'rr,

of the city of lVinnipeg, in the Province of Manitoba,' Canada,: have invented certain new and usefullrnprovements in Flre Pots,

"of which the followingisth'e specification. 'The invention relates to improvements in fire pots of stoves, furnaces andthe like and the principal object'of th'erinventionis to provide a means-insertable or contained within thefire pot which will renderit possible; .by proper firingfto. get an effective combustion of the' fuel; thereby rendering the furnace more efficienta'nd saving materially in the consumption off-fuel and rendering it. possibl'eto burn" low grade and slack coals in house'furnaces without the dangerof exploding gases; 1

' vWVith the above -0b]ect' in view the invention consists essentially in a divisional member inserted n the fire pot 'andcrossrng the sameitov d1v1dethe'fire, the parts belng arranged and constructed as hereinafter more particularly descrlbed and later pointed out in the appended claims, reference be ng had to the accompanying drawing in'whicht 1' represents a vertical sectional view through-the fire pot and combustionchamher for bHIIllIl" the ases of afurnace showing my invention installed. Fig. 2 represents a sectional v ew through the fire pot and combustion chamber, the

' matically the fire in 'sevefa-lxstages;

section b'eing' taken in the plane denoted by the line X-X Fig.

Figures 3 at, 5 and 6 r ai' esentd agram- In the drawing like characters of reference indicate corresponding. parts in. the

more compartments.

several figures. V

' 1 represents a furnace of which 2 1s the fire pot, 3 the'fire door, 4: the customary .tapered to fit thei cu'stomary tapering sides of therfire pot." The length of the plate" is 7 such that lt sits in-the'fi'repotwiththelower- V p abovethe grates to allow of a firebe'd under e fuel 7 ninnrow.

e Specification' of iietters Patent. 1 V

' Application filed September 26, 1 91s. serialifioi '25533151 7 bed but'the bottom of it iskept-clear of the V grates a distance sufiicie'nttoallowof a con- '55 y tinuous bed of fire'unde'ri the- 'st1aicture. H

"The said structure i s"i'ndic'ated iii-' the j drawing at 6 and comprises a divisional plate 'of fire. brick or cast iron which passes acrossthefi're pot'andhas the ends thereof edg -:7 thereof -elevated 'a short distance the structure;

'-The invention is particularl usefulfor I burning soft coal aaby; utlli'iingit Lament "abledtoreleasefthe gases and 'ini'x'them with a'sufiicient quantityfo f airfto support coin;

bustion and'Jto create a high temperature which W111 ignite and b rn the gases.-

In building affire in my'firepot the coal Then coal is thrown into say the left hand side of the pot up to say: the level of the top 'Of the divisional board in which c'ondition it is showman 1. lViththiscondition "it-will'b'e seen that at the right hand sidelof-V is initiallyj'built 'on tlie grates up tor or slightly above the level of the lower edge of the divisionalimeniberfand 'is -initiallyfired."

the divisional member Iha've acornpara- Lively low firebed which is burning freely owing to the factthat anip le airdraftpasses therethrough; such coming? up through the grates and that at'ith'e left haiidj side where As the fire continues burning the icoal heat coming from the more or-less intense fire atthe-lright hand side. V

It isa well known fact that the gases given off from the fuel especially soft coal of high volatile content must be"properly mixed with the'oxygen of the air which is admitted over the fire, in order to consume thefsame gases. There arevarious means in present-day practice of mechanlcally mix? ing these gases and air, such as with fans, air jets and steam'jets in order to obtain the proper combustion.

thereis'Qnotsuch' adraft owing the n- "fif 'ese d i f mi e, Ti -X. 1 gradually frointhe bottom. o V

v .on the left hand side becomes heated andi liberates the gas, 'the'greater apart of the may not project above the top of the fuel It is alsowell lmow'n that a hot'body will create a current ofj moving gases upward" 3 p V over and off the top of same, this in turn causes the unconsumed gases from the coal and the cooler air which has been admitted into the furnace to flow down towards the hot divisional member where upon mixing with the hot gases arising from same becomes ignited.

7 Another feature of my invention is the process of distilling the volatile gases out of the coal before the fuel is burned in the fuel bed. Owing to the nature of the structure of the partition, heat is transferred slowly through the same. When the fuel is first placed in the fire pot at one side of the partition, the slow rise in temperature of the fuel, distils the moisture out of the fuel before the combustible gases are driven out and as they are driven out without coming in contact with the burning fuel they are dispersed without lowering the temperature of the fire bed. The second period of distillation drives out the combustible gases, and after these are all distilled the fuel burns in the bed of the fire in a similar-manner to coke or hard coal.

Due to the location of the division member in the bed of the coal and the comparatively slow transfer of the heat from one side to the other, one side may be at a necessary high rate of combustion. When this side is burned down'the other side has automatically attained a similar high rate of combustion thus allowing a much longer period between firing without attention.

In Fig. 8 I have shown diagrammatically the appearance of the fire a short time after firin where it will be observed that. approximately half the coal in the 'left hand side of the pot has been coked. In Fig. 4

I have shown the coal in the left hand side of the pot entirely coked.

When the fire is in the state as shown in Fig. 4 the fireman then fills the right hand side of the pot with new coal as shown in Fig. 5 and the gases from this coal are driven off by the intense heat developed in the left hand side of the pit and are consumed.

Fig. 6 shows the state of the fire as it would appear with both sides coked and as it would be left, say for the night.

This alternate firing to opposite sides of the divisional member is continued as long as the furnace is in use. g

I have not shown any particular means for bringing in new air on the top of the fire and it is to be understood that sufficient air for proper combustion leaks in around the fire door and through the grates.

lVhilst I have shown a single divisional member, it will be readily understood that the fire pot could be divided up into more thantwo compartments and that thecoal could be firedfinto the various divisions one after the other as explained in connection with the two divisions.

7 Further, whilst I have shown'the divisiona], member as a single piece I wish it to be understood that it could be made in sections' fitted to accommodate contraction and expansion. V

lVhat I claim as my invention is A fire pot having a centrally positioned vertically disposed divisional member of refractory material crossing the same and di viding the pot into two distinct firing compartments opening at the top to a common combustion chamber and with the divisional member elevated above the grate to permit of a single continuous bed of fireunder both compartments.

Signed at Winnipeg, this 7 day of September 1918.

GEORGE ROBERT PRATT. In the resence of- G. .RoxBUReH, j K. B. WAKEFIELD; 

